Tobacco delivered for processing may occasionally contain foreign matter such as pieces of a container in which it is shipped and/or stored, bits of string and paper, foam, cardboard, foil, and/or other items. There is a need for methods and systems to remove foreign, non-tobacco related materials from tobacco prior to its incorporation into tobacco products. Further, there is a need for such methods and systems to be capable of conducting on-line detection of non-tobacco related materials, in real-time, without requirements for extensive computing resources or limited belt speeds.